We report a case of gastric anisakiasis infected with forty worms. A 53-
year-old male under chronic hemodialysis therapy was hospitalized because of nausea,
vomiting and epigastralgia. These symptoms developed about two hours after the patient
had eaten Saba-sushi. He also felt an itch on his back. An endoscopic examination,
performed in the morning of the next day, revealed erosive gastritis accompanied by forty
larval nematodes. We made a diagnosis of gastric anisakiasis. Twenty worms were
removed from the stomach by a biopsy clipper. The remaining twenty worms were left in
the stomach, because the patient was not able to tolerate to a prolonged endoscopic
examination. However, clinical symptoms gradually disappeared in a few days, although
some itches recurred on his face, abdomen and back. The endoscopic examination,
performed on the fifth hospital day, revealed almost healed gastric mucosa and four living
worms in the stomach. All of the four worms were removed endoscopically. Although
gastric anisakiasis is the most common parasite disease of the gastrointestinal tracts, most
cases of gastric anisakiasis were infected with one or two worms. The present case of
gastric anisakisiasis infected with forty worms is relatively rare.